Heat in the Environment

Conduction

Transfer of heat through direct contact between materials, occurring in solids where particles are closely packed.

Convection

Transfer of heat through fluids due to the movement of the fluid itself, where warm fluid rises and cool fluid sinks.

Radiation

Transfer of heat in the form of electromagnetic waves that can occur in a vacuum without requiring a medium.

Greenhouse Effect

Caused by greenhouse gases like carbon dioxide (CO₂) and methane (CH₄) that trap heat in Earth’s atmosphere.

Insulation

Material that stops or slows heat transfer, keeping warmth inside homes and reducing energy costs.

Conductors

Materials that allow heat to pass through easily, such as metals.

Insulators

Materials that resist heat flow, such as styrofoam, wool, or fiberglass.

Thermal expansion

The process by which materials expand when heated.

Expansion joints

Structures in bridges that allow for expansion and contraction due to temperature changes.

Carbon footprint

The total amount of greenhouse gases produced to directly and indirectly support human activities, usually measured in equivalent tons of CO₂.

Energy efficiency

Using less energy to perform the same task, which reduces overall energy consumption.

Renewable energy

Energy sources that are naturally replenished, such as solar, wind, and geothermal.

Non-renewable energy

Energy sources that can be depleted, like oil, gas, and coal.

Why black clothes feel warmer

Black absorbs more heat from radiation than light colors, making you feel hotter.

How to reduce heat loss in a home

Strategies include adding insulation, using weather stripping, and closing curtains at night.

Why some materials feel colder than others

Metal feels colder than wood because it is a better conductor of heat, pulling heat from your hand more quickly.